I did bleed the brakes and I changed the master cylinder and put the correct type of fluid. After I put the new master cylinder and I had the same problem I did install the old master cylinder back same problem

You still have air in the system.(not bled properly) If you let the Master cylinder drop down to nothing then you need to bench bleed that before bleeding the lines again.

Are you able to bleed the brake from the caliper you changed? If you can you may have a plugged bleeder at the master cylinder or the new one did not get drilled all the way through so the fluid comes out. Does the truck have ABS brakes? I am assuming so but not sure, if so you may have to reposition the valve in the line that cuts off the leak and shifts the fluid to the rear wheels in this case, it is in the lines, but at that I would think you still should be able to bleed the master cylinder. You may need to bleed all of the wheels before you can bleed the master.

Don't know how you knew the master cylinder needed
to be, or why it was replaced

They don't fail as often as you hear about reading this
type of web site

If you had braking issues & a fairly decent brake pedal
before new parts went on,then the system wasn't bleed correctly.

I never bench bleed any master cylinder

As you walk it to the vehicle all the fluid runs out,
so why bother,just bleed all 4 corners & your done

fill master cylinder, start at right rear. the way I do it is make sure cap is back on master cylinder. pump the brakes a few times then hold them. have another person open the bleeder valve at the tires until brakes go to floor. hold them down until bleeder is retightened but be sure master cylinder is not out of fluid. then go to left rear and do the same procedure, then right front, then left front. check fluid and if air is all out there should be brakes. good-day ! THIS IS HOW I HAVE ALWAYS DONE IT ! heres a little trick of sorts. you can change a master cylinder, and if you bench bleed it first. and no fluid is lost from the master cylinder lines you do not need to bleed the whole system. but make sure cylinder is full of fluid before putting on vehicle and all air is out of master cylinder.

you must have a lot of air in system. the brakes need bleed to let the air out of system. did you bench bleed the master cylinder before putting it on car ! if not thats why no brakes. to bench bleed a new master cylinder, put it in a vise. fill it full or the proper level of brake fluid. push on the plunger with a dowel or another object. pump it till all air is out of master cylinder, you can tell when no air. it will be all fluid coming out of cylinder. keep checking brake fluid in master cylinder.make sure you push plunger in all the way.when all air is gone replace on car. if you do not loose any fluid from the master cylinder lines, then you can replace it without having air in system. bleed each wheel if needed. good-day!

Is the master cylinder good? a bad master can cause this also did you bleed the master first before bleeding at the wheel and also make sure the bleeder screw is clean, if the hose is good then theres only a few things, a bad master or a master that wasnt bleed, try bleeding the master first then try rebleeding the brakes.

Booster is okay, you have to bench bleed the MC, first. So, since it is installed, bleed it with a kit from the parts store, little plastic hoses screw in to the brake hose fittings, and put other end under fluid in reservoir. pump slowly, especially wait at end of release, for fluid to refill piston chamber....pump until no bubbles...

FROM THIS POINT you must not allow fluid in reservoir to go low, or start all over again....

Now bleed the brakes and you will eventually get pressure.

Hi there,

The pads are easy to change. You do not need any special tools. If there are no grooves in the rotors I would just put on new pads. Don't get cheap pads or they will squeek. I would strongly suggest that you flush out the old brake fluid. You will be amazed at how brown and gunky the old fluid is. Flushing the fluid regularly will help make your calipers and master cylinder last a long time. I like to use Valvoline Synpower brake fluid, it is a couple bucks more but it is DOT 4.

One last tip. When compressing the brake caliper piston you do not want to push the fluid back up to the system, because you might get some crud into the ABS module. Therefore, when compressing the piston, loosen the bleed screw to let the fluid flow out of the bleed screw.

This is how to get it done:

• Remove the old fluid from the master cylinder resevior with a turkey baster. Top up master cylinder with fluid.
• Remove the right rear wheel and bleed/flush the brakes with the old pads on. Top up master cylinder with fluid(important). Remove the caliper, open the bleed screw and compress the piston, close the bleed screw.
• Install new pad and caliper
• Bleed again. Top up master cylinder with fluid.
• Repeat on remaining 4 wheels RR, LR, RF, LF.

Glad to be of help!!!

Indicates air still in the system. I suggest that you start at the master cyl, remembering to keep it full during & after each attempt at bleeding the system and to only fill it by using a funnel & allowing the brake fluid run down the side to eliminate new air being put into the system.

Bleed the master cylinder first by loosening those brake lines while someone has pumped up the system & is holding the pedal to the floor. Make sure your assistant is not releasing the brake pedal before you are tightening the lines each time after bleediing the system, and that all brake pedal movement is done slowly, especially releasing the brake pedal. It causes fluid to rise into the air, bringing air back into the fluid.

Next, go to the farthest brake away from the master cylinder & bleed it, working yourself to the next farthest until you finish with the closest brake. This prevents air from switching lines on you during the process.

If there are no leaks & you have followed this method, there shouldn't be any air in the system & your brakes should be good.

Double check inside the truck to see if there is brake fluid coming from the new Master cylinder behind the brake pedal, that indicates the new seals didn't seat properly.

good luck

You need to make sure you have an assistant. The assistant keep adding fluid and pumping the brakes while you operate the bleeder screws.

The procedure--LF,RF,LR,RR (left front, right front,etc). You are moving from the shortest brake line closest to the master cylinder to the longest brake line furthest from the master cylinder. Use an aquarium air hose (12 inch length), and a clear jar to catch the brake fluid. When no more bubbles escape through the hose, the caliper or cylinder is properly bled.

If the level drops below the LOW mark, air may reenter the system. Keep the reservoir full by checking after each bleed!